and get a free3-month e ibd™ subscription when you call 1-888-280-0149 now. optionsxpress by charles schwab. >>> etfs, exchange traded funds, are more popular than ever, $188 billion invested into etfs last year alone. a record $1.4 trillion parked in etfs right now. all day today on cnbc we've got a very special look at etfs. the latest developments, biggest players. bob pisani who loves etfs. >> loves them. >> live exclusively at inside etf in florida. that's why he loves the conference, because it's florida in the middle of january. no it's february. it's the world's largest etf get together. be sure to check out etf.cnbc.com for etf strategies that you're not going to find anywhere else. to get things going, what do you think will be the hottest etf asset class this year? u.s. equities, bonds, international markets? tweet right now, use #insideetfs. the head winds to real estate may be turning. is real estate godfather robert shiller as enthusiastic as investors? joining us now on the "squawk" newsline, bob shiller, professor of economics at yale university, cofunder of the case shiller